Do not initiate during acutely deteriorating or life-threatening COPD episodes; intended as maintenance treatment and not for relief of acute symptoms Inhalers can produce paradoxical bronchospasm that may be life-threatening; if this occurs, treat immediately with an inhaled, short-acting bronchodilator and discontinue revefenacin Caution with narrow-angle glaucoma; instruct patients to contact physician if symptoms occur (eg, eye pain, blurred vision, visual halos, colored images, red eyes from congestion, corneal edema) May worsen urinary retention, especially with history of prostatic hyperplasia or bladder-neck obstruction Immediate hypersensitivity reported; discontinue drug immediately